Coin operated machinery for vending goods or services in response to insertion of predetermined amounts of coin money are in wide, spread use both in the United States and throughout the world. Since one of the principal objects of constructing these machines is that they may be operated while unattended by the owner, the unforunate but inevitable result has been that a large number of people attempt to cheat coin operated machines. Among the common forms of cheating, or attempting to cheat, coin operated machines are the use of slugs and the technique of "stringing."
The use of slugs is based on use of a non-coin piece of metal of a size identical to, or substantially similar to, the size of a valid coin. It is inserted into the machine in an attempt to operate it. Stringing is a cheating method whereby a piece of string is wrapped around the outer diameter of a coin and is used to lower, and then attempt to remove, a coin from a vending machine so that the mechanism responds to insertion of the coin but the coin does not drop into the coin box.
Since the invention of the transistor, more and more vending machines are using electronic apparatus in coin validators. For example, co-pending application Ser. No. 525,997 filed 8-24-83 now U.S. Pat. No. 4,509,633, entitled "Electronic Coin Validator With Improved Diameter Sensing Apparatus" owned by the assignee of the present invention, discloses an improved electronic coin validator with an improved diameter sensing apparatus using only two coin sensors disposed along a coin's path of travel through the validator which ascertains the coil's diameter by calculating the average velocity of the coil as it passes the sensors.
Among the advantages of electronic coin validators are greater reliability, and the fact that such electronic coin validators may be designed to be much more immune to the use of slugs than many mechanical validators. For example, slide type mechanical coin chutes are virtually unable to detect slugs if the diameter and thickness of the slug are the same as that of a valid coin. Electronic coin validators such as in the above-described co-pending application provide various arrangements for detecting not only the diameter of coins but also electronically sensing the metallic content of the coin as it traverses a predefined path along the runway through the validator.
Additionally, the use of modern electronics in coin validators has allowed arrangements wherein a single coin path for accepting all coins may be defined, but wherein the validator can detect the presence of a plurality of different denominations of coins having different metal content and different diameters. The apparatus described in the above-referenced co-pending application discloses a validator apparatus wherein there is but a single coin path for accepting all coins, and wherein valid coins are allowed to leave the coin path and exit downwardly from the coil path into a coin receptacle or box.
Many existing coin operated vending machines employ a coin meter case for housing a coin-slide type coin validation apparatus. Such coin meter cases are frequently found in laundry washing machines. Conventional coin meter cases typically include a vertical front wall for mounting and supporting the coin slide apparatus, and for supporting the discharge openings of the coin slide apparatus above an interior horizontal floor of the coin meter case. The interior horizontal floor typically includes a coin box opening for allowing valid coins from the coin slide to drop into a coin box positioned in the coin meter case beneath the floor. Accordingly, the vertical front wall of the coin meter case includes a cut-out opening for receiving that portion of the coin slide apparatus to be positioned over the coin box opening, and thus includes a portion of the vertical front wall which extends to a predetermined height above the floor to define an opening in the front wall.
Because of the widespread use of coin meter cases of this type, and the difficulties encountered with conventional coin-slide type validation apparatus, there is a need for the newer type electronic coin validation apparatus to be adapted for use with these existing conventional coin meter cases. However, because of the unique geometry of the coin meter cases, electronic coin validators such as shown in the above-referenced co-pending application cannot be adapted for use with these conventional coin meter cases, principally because of the space and mounting constraints.
If the coin meter case is not physically altered to receive electronic coin validator apparatus, the front wall opening in the coin meter case defines a boundary which limits the ability to return a coin if the coin proves to be bogus. If the coin is allowed to travel beyond the front wall boundary during the examination or validation of the coin, the coin may not have sufficient vertical drop along the path of travel to maintain the coin's velocity to return the coin. Thus, the geometry of unaltered coin meter cases is such that there is a limited vertical space within which a valid coin must be detected and allowed to pass beyond the front wall and thence into the coin box, or rejected prior to passing beyond the front wall so that the bogus coin can be returned to the coin return opening.
Accordingly, there is a need in the art to provide an improved coin validation apparatus which allows the detection and acceptance or rejection of a coin in a limited vertical and horizontal space, such as in a conventional coin meter case wherein the coin must be accepted or rejected prior to the passing of the coin beyond the front wall. It would be preferable to provide for coin validation without altering the coin meter case.